Filter



Jan. 25, 1949. H. HEB@- FILTER Filed Sept. 13, 1944 Q s L Patented Jan.25, 1949 UNITED STATES PATENT OFFICE FILTER Halfdan Hobo, New York, N.Y.

Application September 13, 1944, Serial No. 553,911 (c1. 21o- 167) 4Claims.

This invention relates to. lters in general, and particularly toself-cleaning lters, and to the method whereby filters may be renderedcontinuously self-cleaning. My invention particularly concernsimprovements in iilters adapted to filter or' strain rapidly andcontinuously large quantities of lterable matter containing solids,which latter are intended to be continuously excluded from thefilterable matter as it fiows through thedevice, vwithout therequirement of frequently stopping the operation for the purposeordeniounting and cleansing the lter unit employed therein.

Broadly speaking the principle of my invention comprises a substantiallyclosed vessel equipped with inlets and outlets and in which vessel isremovably secured Va filter unit. The latter comprises a relativelyflexible filter member which is normally "held in substantiallystretched position or under tension by an operative support in the formof a helical spring, which latter is brought under slight compression bythe iilter member itself. AThe spring support for the lter member isforcibly held at one end within the vessel, while its Vother end andthemajor part of its body is vrendered operative, that is compressible andexpansible within certain limits, so that when a lterable matter entersthe vessel andpasses through the lter member, the

support will be causedj to be alternately compressed and released,thereby alternately relaxing and stretching, respectively, the iiltermember supported by it. l y

The operation ofthesupport may-either depend solely upon'the'movementimparted to the lter unit by the passing-through' ofthe filterablematter under pressure, or by auxiliary mechanical means. `However, ineither event the operativeness of the'filter member support is dependedupon .toalternately relax and stretch the-filter member in rapidsuccession, whereby the solids accumulating at one face of the ltermember are rapidly Ashakenoffffand out' of the way of the in-ilowing newiilterable matter.

The method of imparting a combined vibratory, relaxing and stretchingmovement to the ilter member at every point of its exposed area, whilefiltrate is passing therethrough, facilitates a continuous use of thefilter mechanism for extended operating periods. a The prime "objectsoifthe present invention therefore are 'thefprovision of a `i'llterng orstraining devicev wherein the ltering unit is subjected to :a'continuousfalternating reciprocal movement, rand; the' methody whereby.'through 2 such movement of the filtering unit, the solids of thelterable matter will be continuously removed from the filtering materialas new ilterable matter is forced therethrough.

Another object of the present invention is to provide a mechanismconsisting of a substantially closed vessel, and wherein is operativelysuspended a lter unit forming a mobile chamber composed of a resilientsupport and a pliable lter member exteriorly covering it, andconstituting the wall of the chamber, said filter member `being somounted over the support that it somewhat compresses the latter andbrings it under slight tension, while the filter member in turn isnormally held in a stretched position by the compressed support. Thebody of the filter member may relax only then when the support iscompressed in excess to its compression normally induced by the mountingof the lter member.

Another object of my invention is the method of automatically andcontinuously cleansing a lter while in operation, that is whilefilterable matter ows through the lter, which method comprisesactivating of the iilter so that the solids of the iilterable matter tobe treated are continuously removed from the surface of the filterthrough which the filterable matter is to pass.

A further object of this invention is the method of cleansing a filterwhile lterable matter is passed therethrough, which consists ofsubjecting the lter material to a combined vibratory, stretching andrelaxing movement, whereby all points of its effective area rapidlychange their bodily positions, thereby preventing deposits of solidmatter. f

The foregoing major objects of my invention and numerous other`important objects and advantages thereof will become better understoodfrom the ensuing description of the yaccompanying drawings, which, whileforming part of my disclosure, are held more or less in a diagrammaticalform for explanatory purposes only, and which drawings are subject tochanges and modiiications to conform with the best mechanical f practicein the manufacture of an efficient ltering device.

Before describing the detail constructions of the presently preferredforms of my invention, as shown in the drawings, may I state that I am'well familiar with lter and strainer constructions employing iilters inbag form and otherwise, supported by helical springs or frames ofvarious designs, all of which are intended to keep the lter materialstretched to enhance its filtering capacity, but that I have adapted anentirely diierent principle of employing an evermobile filtering unitWithin a closed vessel for purposes entirely foreign to the type'ofdevices mentioned.

Referring now to the drawings:

Fig. 1 illustrates a vertical through one form of my device;

Fig. 2 is a vertical cross section through a modiied form of my device,employing aV ,concally shaped vhelical spring support; and

Fig. 3 is a cross section through a third modiiication of my device,wherein the vibratory-mov-en ment imparted to the lter unit is caused bya suitable mechanism.

In each of the three modifications illustrated. there is employed asubstantially closed vessel Within which operates Va filter unit.Referring now specifically to Fig. l, numeral I denotes a casingprovided with aremovable cover H which is internally threaded to engagean external vvthread at-the upper end of casing i9, and which /coverisrendered-airtight bymeansr'of -a suitable cross section `gasket i2.'Within vcover -H there :is removablyV secured a bushing i3provided-With astui'ng :box is. rendering the connection between cover ll -andbushing 'i 3 airtight. Connected withfbushi-ng t3 -is a domereserving/as connecting piece ffor outlet pipe |6 and valve-controlledrinser pipe il-T. At the side o1- casing IB there is vprovided-a pipeconnection i8 also controlledeby Y a valve, =While at the 'bottom-'of`the casingthere is removably secured an inlet pipe i9, which latter4rnay-also `*be controlledby a valve', notfs-hownysuch-asillusltrated inFig. 3. All parts vconnectedwithcover vl l-are intended tatie-removable.Atthe interior i end of bushing I 3`is preferably providedan-annudar-groove -2 for the "reception of the upper-end of a filtermember 2-, which is forcibly held in the groove-by a spring Wire -2-27-or any other s-uit- 'ablemeans `Diagonall'y opposite to 'groove 2B -a-seat E23 lis provided-in bushing 23 for accommodating a filter membersupport 24-in the -iformof a `cylindric'ally shaped helicalspring.rIflie upperseated end of spring '24 is relatively immovable, YWhile therest-'f Yof the Aspring body, 'including its' essentially Afree end, isrendered operative in'- afmanner'whichfwill -be'presently explained."The lower end ofispring i254 rests ina groove -25 vprovided 4inend cupf25 which has a smaller exterior-groove 21 or the receptionf'of vtheyfree end of yfilter An'iember l2l, which is heldin #the groove by aspring ring -28 or fsimilarfmeans. The material'oflter mem-ber 2 l is so-secured'at'itszflxed and free ends tolbush- 3 .-adherlngkfto-the eachalternately occurring low pressure period and thereby forcibly stretchlter member 2| to 'its normal position. At that moment any deposit onthe lter member will be forcibly shaken off. The alternate compressionand expansion of heliu cal spring support 24 in axial directionobviously is very rapid so that filter member 2l is subjected to avigorous and continuous movement at every ,point ,of its area. Thatmovement consists of a rapidly alternating'suceessionof @stretching andrelaxing' of the tllter material', whereby the latter is caused toforcefully and continuously vibrate and thus prevents the accumulationof solid de- ;posits. When after a protracted operating period ,of thedevice the solid matter of the lterable matteristo be removed fromcasing Il),V the norlniai-i-rilet wisenrployed temporarily as an outlet,while Aoutlet I6 is temporarily closed by a suitable -valve,-not shown.The valve of conduit I1 is now opened and liquid under pressure ispassed into Vthe Ihollow interioriof the `lter imeniber.- V"The and`Will sdepositithe From there theiisolids :I1-Q v.-to' without. viilter-member may" :valve` of conduit-tsl the casingiinteriorfifl fthe lter:materalrandtt l casingfl. Y

yprogress towar sith ture :In yotlirer .11W-lysisA rofcasingzhi), which't :ation of 'the .liil" "limb manner; f i

An importantffaetmrmtishovrm ing i3 and cup 26, respectively,that'heli'c-al spring i ysupport 2id; lis brought lunder-fslighttension', which `rtension however intended Yto be --suiicient `:for'normally keeping *the* material V'of *filter member '2 l in'stret-chedcondition: Theshape of-ithe-lter Jmember is tubular and ormsa closedibagopen 'at' itsr'xed end. f

Operationl VNihenlterable matter under-pressure enters casing l'ilbywayof the inleti I L9 ,iitexertspressure upon filter member 2i andmomentarily com- :pressesl springV supnort 25; When the .support is thuscompressed' the`e tension exerted? by fit upon `lter member 2i:isireleased andv theinaterialof Amally:present in pumping devices*'carrying-the Y Slterable f matter, I the spring: .-will automatically 1revert to its original vexpande'd1-position. :du-ring` inthe-structure.dsclosedsnilifis 'h' :abone @promessi chausjsfin :the shane 0rconstruction eflthe nd gare-,ideama tpibe :sur us .1 modiiii-:ationsofrdeviceishown wherefore any exaggeration or diminution in the dimensionsof the several parts should be disregarded and should be considered onlyas means to facilitate the explanation of the principle of the device.

Referring now to the modiiied form shown in Fig. 2, there will be againobserved a casing I0 provided with a removable, tightly closing coveril, at the interior surface of which there is provided an annularmounting 29 which is fastened by means of screws 3B or many otherlsuitable manner to the cover. Mounting 29 is provided with an interiorseat 3| and anfexteriorseat r32, the former serving for accommodatingthe iixed end of a conically shaped, helical filter supporting member33. Outer seat 32 serves for attaching the upper or fixed lend of ltermember 34, which xed end is held in the groove or seat by an annulus 35.The free or bottom end of support 33 is lodged in an annular seat 35 ofan end cap 3l, which latter is provided with an external groove 33 foraccommodating the smaller or free end of the conically shaped ltermember. The latter is secured in the groove by means of an annulus 39.

Extending into the hollow interior of the combined lter unit, consistingof lter member 34 andy filter member support 33, is an outlet pipe Il@which is preferably welded into cover Il. At the bottom of casing I il aremovable inlet I9 is provided, which may be equipped with a valve. Thefilter mounting 29 for the filter unit is intended to be removable fromthe cover so that it may be readily exchanged if it is so desired. Whilein this modiiication no additional inlet or outlet means are provided,such as inlet pipes il and I8 of Fig. l, the same may be added if foundadvantageous.

The diierence between the iilter unit construction shown in Fig. 1 andthat illustrated in Fig. 2 resides in their shapes and their operation.With a cylindrically shaped unit there will be only a slight tendencyfor its spring body to swing sidewise, while that tendency is clearlypresent in a conically shaped filter support. Thus in the modiiied formshown in Fig. 2 the vibrations imparted to the iilter member, asexplained in the construction shown in Fig. l, are augmented by aswinging movement of the entire filter unit when iilterable matter underpressure enters casing I0 and is propagated through the iilter and towithout the iilter body through outlet 40. As in the construction of theembodiment shown in Fig. l, the lter member in Fig. 2' is clamped inposition in such a way that spring support 33 is brought under slighttension, which in turn normally causes stretching -of the iilter member.When filterable matter under pressure is introduced, spring support 33becomes compressed and thus momentarily relaxes the filter member untilthe spring again expands to stretch it to its normal shape.

The third modiiication of my invention is illustrated in Fig. 3. In thisform again a closed vessel iii is indicated, which is provided .with aremovable cover ii', the latter being rendered airtight by means of agasket 4I. At the interior of the cover there is provided a threadedextension 152, to which is removably secured a mounting 43 for thefilter unit. Also in this construction is provided an interior seat 44for the iilter member support 45, which in this case again is in theform of a cylinder. There is also an exterior seat 46 to which issecured the fixed end 6 of filter member 4l in the manner explained inconnection with the two previously describedembodiments of my invention.

The-free end of the lter unit terminates in a plateil provided with aninternal seat 49 for the free end of iilter member support d5, while anouter groove 59 accommodates the free end of illter member 4l'. At thecenter of plate 48 there is shown a hub 5I to `which is attached thereduced end of operating rod 52 which extends through a stuiing box 53provided in cover I I' and is engaged by an eccentric 54, or any othersuitable means for actuating rod 52. Passing into the interior of thefilter unit is an outlet pipe 55, which is secured to the cover, as is avalvecontrolled flushing inlet 55. At the side of vessel i9 there willbe seen a valve-controlled inlet 5l, while at the bottom anothervalve-controlled inlet I9 is illustrated. Operating rod 52 in engagementwith plate or filter unit closing element 48 is adapted to cause thelatter to reciprocate when eccentric 54 is turned, whereby iiltersupport ,45 becomes positively compressed and released in rapidsuccession, thus causing filter member 4l to alternately relax andstretch. This positive mechanical movement imparted to the filter unitis very similar to or identical with the movement of the units shown inFigs. l and 2, except that in these two iirst embodiments I dependsolely upon the force of the iilterable matter to induce the desiredmovement, whereas in the third modification the vibratory operation ofthe unit is controllable and may be adjusted to either increase ordecrease the movement by varying the stroke of rod 52.

A positive mechanically induced operation of the iilter unit isadvantageous for filtering devices of relatively large dimensionsintended for large iiltering capacities. However the operating principleof the filtering unit in every one of the forms shown remainssubstantially unchanged, and it is my intention therefore to employ anyone of the devices for treatment of i'ilterable matter for which theyare best suited, depending upon the characteristics and the quantity ofiilterable matter to be processed.

It will be noted that the outlet pipes in all three embodimentsillustrated in the drawings extend substantially throughout the entirelength of the iiltering units and terminate in relatively closeproximity to the movable ends of the units.

While only three embodiments of my device are shown and described, be itunderstood that changes and improvements may be required to meetspecific conditions without departing from the broad scope of myinvention based on the principle of a combined vibratory and alternatingstretching and relaxing movement is imparted to the lter member whileiilterable matter passes therethrough, whereby sediments and solids areautomatically removed from the filter material. Having thus described myinvention, I claim:

I claim:

1. In a self-cleaning iilter construction, an

4elongated vessel adapted for use in vertical position and having acentral opening at its bottom, a removable, airtight closure for the topof the vessel, a mounting for a filter unit extending coricentricallyfrom the closure into the vessel and having interior and exteriorgroove-like seating means, a filter unit depending from said mountinginto the vessel and comprising a helical spring element resting with itsupper, relatively fixed end against said interior seating means, apliable,

substantially v.tabular siiter `nuernber V-.suppo1'.te'cl `by `asinixteriorly covering .saidspring element, the

upper, relatively Xed-.end'o the filter :member 1being;:seeuretl -insaid exterior .seating means of 'said .c1osure:mounting, z:exelosirlgmember et the endet the Llter member being Aiiiiedlysecured in saidlower seating .means -of the closing member, an .outlet `.eonduitextending through .the Vessel 4closure uinto the yfilter lunit; Vv:mdterminating .in near LproXimityto-said closing member, .said itermemberslightly .compressing vserial spring element.

.2.-.In azself-cleaning filter, as set iorthin claim .1,said lter memberand .its .supporting Vspring .member 'being of :a .sbstantially.cylindrical formation.

'311.111 asel-cleaning filter, as setiorth in claim.

1,:sa'`dl1ter member Vamd its .supporting spring memberbingof a.substantially conical formation.

4.11n..2se1-o1eaningflter, as `per claim l, .and reciprocating means`extending through the vessel closure .anlgbeing .attached 11o/.said.closing .member .for imparting motion to lthe lter unit.

HEBO.

REFERENCES CITED A` Theife'llowing .references are of record in the fueAo this patent:

i0 STATES 'PATENTS Number VName g Date V1,094,321 y. Finch,Jr Apr. 21,1914 Y :1,324,635 .Ascoli.. .u Dec. 9, 1919 V1,607,027 Wall Now/116,1926 V..15 .1,696,313 Liddell i Dee. 25, 1928 :1,757,834 -Haegler 1 May6, 1930 `'1,760,764 l-Merrell et al. May 27, 1930 1,806,513Straus-ScharrineJ May 19,1931 .2,031,589 A. .Burckhalter et al. Feb..25, 1936 ,.20 ,2,162,043 Westlund .et al.i June 13, 1939 2,167,236-Giese1er. g r fJuly 25, 1939 FOREIGN PATENTS Number 'Country Date 25467,511 Germany Oct. '25, 1928

